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0 02-02-2002 Approved Issuerev. date Description/issued for
prepared authorised
client: ADWEAproject: STANDARD SPECIFICATIONS FOR WATER
WORKStitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 1 of: 16
SPECIFICATION FOR TRANSFORMERS
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Client ADWEAProject: STANDARD SPECIFICATIONS FOR WATER
WORKSTitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 2 of: 16
Table of Contents page
1.
SCOPE...................................................................................................31.1
General........................................................................................3
2. APPLICABLE
STANDARDS.................................................................32.1
IEC Standards
.............................................................................32.2
Other Standards
..........................................................................32.3
Local
Standards...........................................................................3
3. SITE
CONDITIONS................................................................................43.1
General........................................................................................43.2
Altitude
........................................................................................43.3
Special Design
Conditions...........................................................4
4. DESIGN CONSIDERATIONS
................................................................44.1
General........................................................................................44.2
Ratings
........................................................................................54.3
System
Variations........................................................................54.4
Temperature
Rise........................................................................54.5
Impedance Voltage and Short Circuit Currents
...........................54.6 Vector Group
...............................................................................54.7
Noise
Level..................................................................................54.8
Installation
...................................................................................6
5. CONSTRUCTION
REQUIREMENTS.....................................................65.1
Internal
Arrangement...................................................................65.2
Tank or Enclosure
.......................................................................65.3
Windings......................................................................................65.4
Insulation
.....................................................................................75.5
Oil and Fillings
.............................................................................75.6
Terminals.....................................................................................75.7
Cable Connection
........................................................................85.8
Off-Load Tap
Changers...............................................................85.9
Earthing
.......................................................................................95.10
Fittings and
Accessories..............................................................95.11
Rating
Plate...............................................................................13
6. INSPECTION AND TESTING
..............................................................146.1
Inspection
..................................................................................146.2
Testing.......................................................................................14
7. PACKING AND SHIPMENT
................................................................15
8. VENDOR DOCUMENTATION
.............................................................15
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Client ADWEAProject: STANDARD SPECIFICATIONS FOR WATER
WORKSTitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 3 of: 16
1. SCOPE
1.1 General
This specification covers the general requirements of Medium
Voltage to Low VoltageDistribution For Transformers for the water
works project. This specification sets theminimum acceptable
requirements for design, construction, testing and delivery
oftransformers.
In case of differences between this specification and the
international standards specified inclause 2 below, the more
stringent requirements shall prevail.
2. APPLICABLE STANDARDS
2.1 IEC Standards
Unless specified otherwise transformers shall conform in design,
material, construction andperformance to the latest editions of the
IEC Standards and in particular to the followingpublications:
- Power transformers IEC 60076- Thermal evaluation and
classification of electrical
insulation IEC 60085- Insulating liquids determination of the
break down
voltage at power frequency IEC 60156- Specification for unused
minerals insulating oils IEC 60296
for transformers and switchgear- Loading guide for oil-immersed
power transformers IEC 60354- Determination of transformers and
reactors IEC 60551
sound levels- Dry type power transformers IEC 60726
Note :In case Transformer terminal box is provided with CTs then
relevant IEC standard for CTis also applicable.
2.2 Other Standards
If different standards, namely BS or VDE are specified on the
data sheets and/oraccompanying documents, the latest editions of
the specified standards shall be applicable.
2.3 Local Standards
Further to the international standards, transformers shall in
any case conform to the localstandards (ADWEA), if these are
higher, more stringent or of special nature and shall bepreviously
approved by ADWEA.
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Client ADWEAProject: STANDARD SPECIFICATIONS FOR WATER
WORKSTitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 4 of: 16
3. SITE CONDITIONS
3.1 General
For general climatic conditions applicable to the project
installations, refer to Specification forGeneral Technical
Requirements.
3.2 Altitude
Altitude where transformers will be installed shall not be more
than 1000 metres above sealevel.
3.3 Special Design Conditions
The transformers shall be designed for an ambient temperature of
55 deg. C in outdoor areaswithout sunshade.
4. DESIGN CONSIDERATIONS
4.1 General
4.1.1 Purpose of Equipment
All components utilised in the construction of the transformer
shall be of latest design, newand in current production. Material
and equipment shall be approved by the appropriateauthority where
applicable.
- The power/distribution transformer will be used to supply
power to the electrical systems.
The design shall allow continuous full load operation of
complete transformer underconditions specified.
4.1.2 Safety and reliability
- The transformer shall be of a standard, well tested and proven
design which ensuresmaximum safety to personnel, maximum service
reliability and economic operation for anoperational lifetime of at
least 15 years. Design and construction shall be simple andshall
provide good accessibility to components and parts.
- All equipment, materials and parts shall be brand new and
unused, of currentmanufacture, of modern design and of the highest
industrial grade, free from allimperfections that might affect the
performance.
- Transformers feeding frequency converters shall be provided
with static screening tosuppress the radio frequency interference
(RFI).
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Client ADWEAProject: STANDARD SPECIFICATIONS FOR WATER
WORKSTitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 5 of: 16
4.2 Ratings
4.2.1 Standard ratings
Transformers kVA and voltage rating shall comply with the
preferred values of the standardsspecified. Unless otherwise
specifically stated to the contrary the rated kVA shall be based
onnatural air cooling. Voltage insulation of windings shall be for
unearthed system.
For oil immersed and dry type transformers manufacturer shall
indicate the base rating of thetransformer for operation in an
ambient of 40C and furnish the de-rating factors forequipment
rating at different ambient temperatures.
4.3 System Variations
Transformers shall be capable of continuous operation at their
maximum kVA ratings andwithin their limits of temperature rise at
system continuous deviation of up to and including thefollowing
percentage values of the rated system :
- Voltage : 10%
- Frequency : 5%
4.4 Temperature Rise
Temperature rise of the oil immersed type transformers shall not
exceed the following valueswhen operating continuously at the
maximum kVA ratings, at the rated voltage and frequencyand with the
provisions of clause 4.3 and climatic/installation conditions of
clause 3.0 above:
- Top oil temperature risemeasured by thermometer 50C
- Winding temperature risemeasured by resistance 55C
4.5 Impedance Voltage and Short Circuit Currents
Unless parallel operation with existing transformers, having
different characteristics, isspecified, transformers shall have the
impedance voltage and short circuit current values asper IEC
requirements or as indicated in the data sheets.
4.6 Vector Group
The vector group shall be as specified in the data sheets.
4.7 Noise Level
The noise pressure level produced by transformers operating at
the rated voltage andfrequency at either no load or full load shall
be below the level specified in IEC unlessspecified otherwise on
the data sheets.
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Client ADWEAProject: STANDARD SPECIFICATIONS FOR WATER
WORKSTitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 6 of: 16
4.8 Installation
Unless otherwise specified in the data sheets or accompanying
documents transformers shallbe suitable for outdoor installation
(without sunshade). Ventilation requirement for indoorinstallation
of dry type transformers shall be specified by the
manufacturer.
5. CONSTRUCTION REQUIREMENTS
5.1 Internal Arrangement
Transformer core shall be of robust design adequately braced to
prevent displacement due toelectromagnetic stresses of short
circuits, and the mechanical shocks of normal moving andhandling of
the transformer without any need for special shipping braces.
The core laminations shall be evenly secured to prevent settling
of the core and minimizenoise and vibration when transformer is in
operation.
The core construction shall be such that removal and replacement
of the coils would requirethe removal of minimum possible number of
core laminations.
5.2 Tank or Enclosure
For oil immersed transformers the tank, cover, radiators and any
other attachedcompartments, shall be rigid steel construction.
Radiator tubes or fins shall be so arranged that external
cleaning and repainting can becarried out at site without
dismantling.
For sealed type transformers the tank cover shall be welded with
continuous joint. Boltedconnection with tack-welded bolts is not
acceptable. After filling the tank with oil the fillingorifice
shall be permanently sealed in a tamperproof manner.
The tank cover, radiators etc. shall have adequate strength to
withstand without deformation.The internal pressure of the oil, air
and gas under operation conditions.
Pressure relief valves, when specified, shall be fitted and set
to operate at static pressure ofless than the hydraulic test
pressure of the tank.
Minimum degree of protection for dry type transformers shall be
IP 31 for indoor installationand IP 55 for outdoor
installation.
5.3 Windings
Transformers shall have separate low and high voltage
windings.
The neutral point of star connected windings shall be brought
out separately to a terminal onthe respective winding side.
The MV winding shall have tapping at 2.5% and 5.0% of the rated
MV voltage unlessspecified otherwise on the data sheet.
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Client ADWEAProject: STANDARD SPECIFICATIONS FOR WATER
WORKSTitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 7 of: 16
The winding coils shall be adequately braced to prevent
distortion of the windings ormovement of the coils on the core
limbs under short circuit condition or normal moving andhandling of
the transformer.
LV winding of dry type transformers shall be made of Aluminium
sheet to reduce axialstresses under short circuit. The layers of
windings shall be insulated by class F insulatingmaterial. The HV
windings shall be made from insulated aluminium wires and shall be
castunder vacuum in filled epoxy resin.
5.4 Insulation
All windings shall be fully insulated and the insulation shall
be free from any composites likelyto soften, shunt or collapse
during service. The insulating material shall be of a type that
doesnot shrink, disintegrate, carbonize or become brittle in hot
oil for oil immersed transformer.
Insulation varnish treatment shall be accomplished by vacuum
impregnation.
5.5 Oil and Fillings
Mineral oil for immersed type transformers shall be Shell DIALA
B,D or AX alternative oilscomplying IEC 60296.
Oil shall be dried prior to filling of the transformer which
shall be performed under vacuum.
PCB synthetic liquids (Poly Chlorinated Biphenyls) or other
chlorinated hydro carbons withtrade names Askarel, Pyranol,
Clapnen, Pyralene, etc. are not acceptable and shall not
beused.
Instructions for cleaning and filtering of the liquid used shall
be furnished with eachtransformer.
The dielectric strength of oil or synthetic liquid shall be more
than 125 kV/cm.
Oil immersed type transformers shall be filled with the oil at
the manufacturers works.
The brand and type of oil shall be stated on the rating
plate.
5.6 Terminals
To provide a 4-wire system, the low voltage starpoint
connections shall be brought out on aseparate terminal.
Terminals shall be marked in accordance with the connection
diagram marked on the ratingplate.
The stems and bushing of the terminals shall be sealed in
leakproof manner into the tank wallor cover, rotations of terminal
stems shall be prevented by effective locking.
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Client ADWEAProject: STANDARD SPECIFICATIONS FOR WATER
WORKSTitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 8 of: 16
External terminals for the connection of cables shall be
provided with bolted type conductorconnections of adequate
dimensions and ratings and if two or more conductors per
terminalare required, provision shall be made to accommodate the
same.
All bushings shall be self-contained and shall be sealed into
the enclosure air/gas and liquidtight with non-deteriorating
gaskets suitable for the liquid used.
All transformers shall be provided with external earthing
terminal. This shall be either athreaded bolt or bolted clamp. The
minimum diameter shall be 8 mm.
5.7 Cable Connection
5.7.1 Cable Boxes
Cable entries into the boxes shall be located such that
conductors can be clamped straightinto the terminal connectors
without being bent into tortuous shapes inside the box.
Extension pieces bolted to the actual terminal with additional
bolted conductor clamps in linewith the cable entry may be
required.
Cable boxes for PVC or XLPE insulated cables shall be dry type.
Single core type cablesshall be glanded to non-magnetic plates.
5.7.2 Terminations and glands
Cable terminations for lower voltages shall be with double
compression type glands. Singlecore cable entries shall be mounted
on non-magnetic plates.
For star point earthing an extra gland, suitable for PVC
insulated cable shall be provided.
5.7.3 Supports and clamps
Cable clamp supports shall be delivered as an option.
5.8 Off-Load Tap Changers
Tap changing on the MV winding shall be done by externally hand
operated off-load tapchanging switch. The switch shall preferably
satisfy the following requirements:
- The switch shall be operable by its handle without the need of
additional tool and withoutrisk to personnel safety.
- The contact changing shall be positive snap action arranged so
that it is impossible forthe contacts to be left in a position
where the circuit remains interrupted.
- The stops shall be robust type to prevent overrunning.
- Padlocking of the switch shall be provided.
- Tap positions shall be clearly marked.
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Client ADWEAProject: STANDARD SPECIFICATIONS FOR WATER
WORKSTitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 9 of: 16
- The driving rod through the tank cover or wall shall be sealed
to prevent leakage of air,gas or liquid under all service
conditions.
5.9 Earthing
MV cable boxes shall have an earthing terminal of adequate
dimensions for the cableearthing wires. LV cables boxes shall have
earthing terminals of adequate dimensions foreach cable earthing
sheath wire.
For connection to the external earthing network, the enclosure
shall have earthing pads withthreaded holes for connection to a 70
sq mm stranded copper earthing cable.
5.10 Fittings and Accessories
The following shall be provided for all transformers as a
minimum:
- Pressure relief device.
- Winding temperature indicator with contacts.
- Oil temperature indicator with contacts (for oil immersed
transformers).
- Oil level switch with contacts (for oil immersed
transformers).
- Lifting lugs for lifting the entire transformer.
- Skid under base with bi-directional rollers.
- Rating plate.
- Any special tools required for erection, operation, or
maintenance of the transformer.
All VENDOR cabling/wiring on the transformer shall be run
through cable trays fitted ontransformer.
Further to the above the following shall be provided for
breather type transformers:
- Air dryer with silica gel dehydration capsule and suitable air
lock to prevent externalatmosphere from coming into direct contact
with insulation liquid.
- Liquid conservator with connection pipe to transformer tank
and extending into theconservator for collection of any water or
sludge. A drain plug shall be provided at thelowest part of the
conservator.
- Liquid level indicator fitted on the conservator.
- Thermometer pocket with sealing cap. Pocket shall be
approximately 150 mm deep and20 mm inside diameter and welded into
the tank wall such that a thermometer orthermoprobe can be inserted
to measure the top liquid temperature even at the lowestliquid
level.
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Client ADWEAProject: STANDARD SPECIFICATIONS FOR WATER
WORKSTitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 10 of:
16
- Gas and liquid activated Buchholz relay with suitable valves
and flanges to enableremoval for maintenance without dismantling
the transformer.
- Filling cap for topping of liquid.
- Valves for filtration and draining of liquid.
- Liquid sampling device, separately fitted or combined with the
drain valve.
Lifting lugs for lifting tank cover with or without core and
coil assembly. If without, further liftinglugs for core an coil
assembly shall be provided.
5.10.1 Pressure Relief Valve
A pressure relief device of sufficient size, capable of
functioning without electrical power shallbe provided for the rapid
release of any pressure that may be generated within the tank
andwhich might result in damage to the equipment. It shall also be
capable of maintaining the oiltightness of the transformer under
all conditions of normal service.
The device shall operate at a static pressure of less than the
hydraulic test pressure fortransformer tanks and shall be designed
to prevent further oil flow from the transformerfollowing its
operation.
5.10.2 Conservator
Conservator shall have an adequate sump, a filling cap and a
drain valve. To permit cleaningof internal side conservator, one
end of the conservator to have removable cover with facilityfor
lifting.
Level gauge with markings to be provided on conservator. The
level gauge to indicatemaximum, minimum and normal level.
The main feed pipe from the conservator vessel to the
transformer shall be connected to thehighest point of tank and
shall be arranged at a rising angle towards the conservator at
about5 degree to horizontal. A valve shall be provided at the
conservator to cut off the oil to thetransformer.
Conservator to be connected to a dehumidifying breather which
shall be mounted at about 1.5metres above ground level.
5.10.3 Valves
Valves shall be of the fully sealing full-way type suitable for
minimum and maximumtemperatures specified without any
deterioration. Valves to open when turned counterclockwise. All
valves other than 'drain' and 'filter' to be fitted with an
indicator readily visiblefrom ground level clearly showing position
of valve. All valves opening to atmospheres shallbe fitted with
blanking plates.
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Client ADWEAProject: STANDARD SPECIFICATIONS FOR WATER
WORKSTitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 11 of:
16
5.10.4 Explosion Vents
Explosion vents with single diaphragm to be provided which shall
be connected toconservator by an equaliser pipe.
5.10.5 Cooling
Detachable radiators with valves to be provided and shall be
through connected to the maintank. Radiator thickness to be 1.20mm
(minimum) and shall be fitted with lifting lugsmachined, flanged
inlet and outlet pipes.
Plugs shall be fitted at the top and bottom of each radiator for
filling and draining. The oilcircuit of all coolers shall be
provided with the following as appropriate to tank mounted
onseparate bank coolers :-
A valve at each point of connection to the transformer.
A valve in the main oil connection at the bottom of each
cooler.
Loose blanking plates to permit the blanking off of the main oil
connection to the top of eachcooler.
A 50 mm oil filtering valve at the top and bottom of each
cooler, the bottom valve shall alsofunction as a drain valve.
A thermometer pocket fitted with a captive screwed cap on the
inlet and outlet oil branches ofeach cooler.
5.10.6 Disconnecting And Sealing End Chambers
Where M.V. cables of rating 11 kV and above are terminated in a
cable box, an air insulateddisconnecting chamber with removable
links shall be provided. The disconnection chambershall have a
removable cover and the design of the chamber shall be such that
ampleclearances are provided to approach the terminations of the
disconnecting links, and alsofacilitates either the transformer or
each cable to be subjected separately to high voltagetests.
Cable termination box shall be provided with suitable
arrangement to provide supportingstructure from floor.
Cables boxes for 6.6 kV and below, need not be attached with
disconnecting link chambers.
All terminal boxes to be provided with bushings with Air
clearance and creepage suitable foroutdoor mounting type
transformer.
An earthing terminal shall be provided in each disconnecting or
sealing end chamber to whichthe connections from the transformer or
reactor winding can be earthed during cable testing.
Terminals shall be marked in a clear and permanent manner.
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Client ADWEAProject: STANDARD SPECIFICATIONS FOR WATER
WORKSTitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 12 of:
16
5.10.7 Temperature Indicating Devices And Alarms
Oil temperature indicating (OTI) devices shall be fitted with
one set of contacts adjustableover the range 60C to 110C for
initiating a DC operated alarm.
Winding temperature indicating (W.T.I.) devices shall indicate
the temperature of the hottestspot of the winding and shall have a
load-temperature characteristic approximating to that ofthe main
winding. Two sets of contacts shall be provided for initiating of
alarm and trip relays.
Separate C.T. shall be used for W.T.I.
Temperature indicating devices shall incorporate a dial and a
pointer indicator and a separatepointer to register the maximum
temperature reached.
The capillary connected sensing bulbs of temperature indicators
shall be positioned inseparate oil-tight pockets arranged in the
top oil.
The temperature indicating devices shall be so designed that it
shall be possible to move thepointers by hand for the purpose of
checking the operation of the contacts and associatedequipment. The
working parts of the instruments shall be made visible by the
provision ofdials and glass fronted covers.
The characteristics of the winding temperature indicating
devices shall be forwarded to theADWEA/ENGINEER for approval prior
to the delivery of the transformers and shall also beincluded in
the operating and maintenance instructions.
All temperature indicators shall be housed in the marshalling
kiosk or box and shall bemounted so that they will not be affected
by vibration.
5.10.8 Bushings
a) The bushing insulator shall be rated for maximum system
voltage and comply withrequirements of IEC.
b) Minimum current rating shall be 400 Amps or as per load,
whichever is higher.
c) In case of overhead line connected transformers, bushing
shall suitable with creepagesfor outdoor and to be provided with
arcing horns.
d) Neutral bushings to be provided for Earthing the neutral.
e) A separate box shall be provided to accommodate neutral C.T.
for restricted fault relay.
f) All bushings shall be marked with symbols as per rating plate
and connecting diagram.
5.10.9 Gas and Oil Actuated Relays (Buchlotz Relay)
Each transformer shall be provided with Bucholtz relay for
operation during fault conditionsresulting in production of
excessive gas inside the tank.
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Client ADWEAProject: STANDARD SPECIFICATIONS FOR WATER
WORKSTitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 13 of:
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This relay is to make an Alarm contact during low oil level
conditions and make trip contactduring upsurge.
The normally open, Electrically separate alarm and tripping
contacts shall not exposed to oil.
The relays shall be fitted in the expansion pipe connecting the
transformer tank to theconservator.
Each relay shall be provided with a test block to take a
flexible pipe connection for checkingthe operation of the
relay.
Bucholtz relay shall be fitted with flange on both ends and a
valve to isolate oil supply forease of removal of the relay and
assembly.
5.10.10 Painting
Paints chosen for Transformer should be carefully selected to
withstand Tropical heat andextreme weather. The paint shall not
scale off, crinkle or removed by abrasion due to
normalhandling.
The surface to be painted shall be shot or sand blasted to
remove all dust and scale orforeign adhering matter. All traces of
oil and grease should be removed by suitable treatment.
All surfaces exposed to outside shall be painted with suitable
anti rust and anti-corrosivepaints.
The colour shall be as per data sheet or subject to
ADWEA/ENGINEER approval.
5.11 Rating Plate
The rating plate(s) shall be of non-corrosive material.
Enamelled plates are not acceptable.The rating plate(s) shall give
the following information:
- The international specification to which the transformer
conforms to.
- Vector group and winding connection.
- Percentage tapping positions of rated voltage.
- Rated MV voltage at zero tapping.
- Rated LV voltages at no load and full load at above
condition.
- Rated ambient temperature.
- Rated kVA at self air cooling at above conditions.
- Rated full load current and short circuit current withstand
for 3 seconds.
- Impedance Voltage at principal tap.
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WORKSTitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 14 of:
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- Rated reactance.
- Make, type, volume, and weight of insulation liquid.
- Enclosure class of transformer.
- Lifting weight of the core and winding assembly.
- Lifting weight of the entire transformer with liquid.
- Transformer type, make, serial number, year of manufacture and
purchase ordernumber.
6. INSPECTION AND TESTING
6.1 Inspection
Visual inspection of the transformer or its parts and
accessories may be required by theADWEA/ENGINEER or authorised
inspector representing ADWEA at the following stages
ofconstruction:
- Before core and winding assembly is placed in the transformer
tank.
- Before final packing of transformer and its parts for
shipment.
The manufacturer has to inform ADWEA/ENGINEER two weeks in
advance of the events'dates.
6.2 Testing
The transformers shall be tested by the manufacturer to the
requirements of the specifiedinternational standards. Some or all
of the tests may be witnessed by ADWEA/ENGINEER orthe authorised
inspector representing them. The witnessed tests shall be indicated
on thetest sheets or accompanying documents and the manufacturers
have to informADWEA/ENGINEER two weeks in advance of the test
dates.
6.2.1 Routine tests
All transformers shall be subjected to the following routine
tests:
- measurement of winding resistance; on all taps
- measurement of voltage ratio on all taps and check of voltage
vector relationship;
- measurement of impedance voltage (at zero tapping),
shortcircuit impedance and loadloss;
- measurement of no-load loss and current;
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WORKSTitle: SPECIFICATION FOR TRANSFORMERS
tender: project: document: W-E-SS-003 rev: 0 sheet: 15 of:
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- the insulation resistance of each winding in turn to all other
windings, core and frame ortank connected to earth shall be
measured and recorded. The coil and windingtemperatures shall be
measured immediately prior to the test and be recorded.
6.2.2 Type tests
The manufacturer shall carry out the following type tests if
requested on the data sheets oraccompanying documents, if not,
evidence of such type tests carried out on similartransformers will
be accepted:
- temperature rise test;
- impulse voltage withstand test (on oil immersed type
transformers).
6.2.3 Special tests
Any one or more of the following tests may be requested to be
carried out on the transformer,if indicated on the data sheets or
accompanying documents:
- measurement of zero sequence impedance;
- short-circuit test capabilities of transformer;
- measurement of the harmonics on the no-load current;
- measurement of acoustic sound level.
7. PACKING AND SHIPMENT
Transformers shall be packed in wooden type seaworthy crates
having sufficient strength towithstand normal ship handling and
transport.
The crates shall be marked with the place of destination, the
Owner's name, order number,type of equipment etc.
8. VENDOR DOCUMENTATION
The following shall be provided by the manufacturer :
- Foundation fixing arrangement drawings(s)
- General arrangement drawing
- Name/tag plate lists
- Component arrangement drawing(s)
- Material lists
- Material descriptive literature
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WORKSTitle: SPECIFICATION FOR TRANSFORMERS
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- Performance data/curve(s)
- Connection/terminal - diagram(s)
- Type test certificate(s)
- Routine test certificate(s)/report(s)
- Weight data sheet(s)
- Transport/lifting instructions.
- Installation instruction(s)
- Operating instructions
- Maintenance instructions
- completed data sheets.
- priced list of spare parts recommended to be on hand during
plant start-up and two (2)years of operation.